Detection rules › Kusto

Progress MOVEIt File transfer folder count above threshold

Severity
medium
Time window
15m
Group by
Computer, ipaddress, userdisplayname, username
Source
github.com/Azure/Azure-Sentinel

'Identifies Progress MOVEIt File Transfers with distinct folder count above certain threshold in a 15min time period. Please note that entity mapping for arrays is not supported, so when there is a single value in an array, we will pull that value from the array as a single string to populate the entity to support entity mapping features within Sentinel. Additionally, if the array is multivalued, we will input a string to indicate this with a unique hash so that matching will not occur.'

MITRE ATT&CK coverage

TacticTechniques
ExfiltrationT1020 Automated Exfiltration

Rule body kusto

id: 26a993ca-0a96-45a0-8405-05a210fb98f8
name: Progress MOVEIt File transfer folder count above threshold
description: |
  'Identifies Progress MOVEIt File Transfers  with distinct folder count above certain threshold in a 15min time period.
   Please note that entity mapping for arrays is not supported, so when there is a single value in an array, we will pull that value from the array as a single string to populate the entity to support entity mapping features within Sentinel. Additionally, if the array is multivalued, we will input a string to indicate this with a unique hash so that matching will not occur.'
severity: Medium
requiredDataConnectors:
  - connectorId: WindowsForwardedEvents
    dataTypes:
      - WindowsEvent
queryFrequency: 15m
queryPeriod: 15m
triggerOperator: gt
triggerThreshold: 0
tactics:
  - Exfiltration
relevantTechniques:
  - T1020
query: |
  let threshold = 500;
  Event
  | where EventID == 0 and Source == "MOVEit DMZ Audit" and EventLog == "Application"
  | where RenderedDescription has_any ("Downloaded", "Uploaded")
  | parse RenderedDescription with * "User '" userdisplayname "' (" *
  | parse RenderedDescription with * "IPAddress: " ipaddress " FileID:" * " FileName: " filename " FolderID: " folderid " FolderPath: " folderpath " Username: " username " AgentBrand: " *
  | summarize count_distinct_folderpath=dcount(folderpath), dirlist=make_set(folderpath) by Computer,userdisplayname,username,ipaddress,bin(TimeGenerated, 15m)
  | where count_distinct_folderpath >= threshold
  | extend DirSample = iff(array_length(dirlist) == 1, tostring(dirlist[0]), strcat("SeeDirListField","_", tostring(hash(tostring(dirlist)))))
entityMappings:
  - entityType: Account
    fieldMappings:
      - identifier: Name
        columnName: userdisplayname
  - entityType: IP
    fieldMappings:
      - identifier: Address
        columnName: ipaddress
  - entityType: Host
    fieldMappings:
      - identifier: HostName
        columnName: Computer
  - entityType: File
    fieldMappings:
      - identifier: Name
        columnName: DirSample
customDetails:
  TransferCount: count_distinct_folderpath
  FilesList: dirlist
incidentConfiguration:
  createIncident: true
  groupingConfiguration:
    enabled: true
    reopenClosedIncident: false
    lookbackDuration: 5h
    matchingMethod: Selected
    groupByEntities:
    - Account
    - Host
    groupByAlertDetails: []
    groupByCustomDetails: []
version: 1.0.1
kind: Scheduled

Stages and Predicates

Parameters

let threshold = 500;

Stage 1: source

Event

Stage 2: where

| where EventID == 0 and Source == "MOVEit DMZ Audit" and EventLog == "Application"

Stage 3: where

| where RenderedDescription has_any ("Downloaded", "Uploaded")

Stage 4: parse

| parse RenderedDescription with * "User '" userdisplayname "' (" *

Stage 5: parse

| parse RenderedDescription with * "IPAddress: " ipaddress " FileID:" * " FileName: " filename " FolderID: " folderid " FolderPath: " folderpath " Username: " username " AgentBrand: " *

Stage 6: summarize

| summarize count_distinct_folderpath=dcount(folderpath), dirlist=make_set(folderpath) by Computer,userdisplayname,username,ipaddress,bin(TimeGenerated, 15m)
Threshold
ge 500

Stage 7: where

| where count_distinct_folderpath >= threshold

Stage 8: extend

| extend DirSample = iff(array_length(dirlist) == 1, tostring(dirlist[0]), strcat("SeeDirListField","_", tostring(hash(tostring(dirlist)))))
DirSample =
ifdirlist == 1tostring(dirlist[0])
elsestrcat("SeeDirListField", "_", tostring(hash(tostring(dirlist))))

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
EventIDeq
  • 0 transforms: cased corpus 2 (kusto 2)
EventLogeq
  • Application transforms: cased corpus 3 (kusto 3)
RenderedDescriptionmatch
  • Downloaded corpus 2 (kusto 2)
  • Uploaded corpus 2 (kusto 2)
count_distinct_folderpathge
  • 500 transforms: cased

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

FieldSource
Computersummarize
count_distinct_folderpathsummarize
dirlistsummarize
ipaddresssummarize
userdisplaynamesummarize
usernamesummarize
DirSampleextend